Enum StreamEvent 

pub enum StreamEvent {
    TextDelta(StreamChunk),
    ThinkingDelta(String),
    ReasoningFinalized(String),
    ToolCall(ToolCall),
    PreExecutedToolCall {
        name: String,
        args: String,
    },
    PreExecutedToolResult {
        name: String,
        output: String,
    },
    Usage(TokenUsage),
    Final,
}

Structured events emitted by model_provider streaming APIs. This extends plain text chunk streaming with explicit tool-call signals so agent loops can preserve native tool semantics without parsing payload text.

Variants

TextDelta(StreamChunk)

Text delta from the assistant.

ThinkingDelta(String)

Transient, human-readable thinking progress. Surfaced to the user (gated by the runtime visibility policy) and never persisted into reasoning_content.

ReasoningFinalized(String)

Durable, replay-only finalized reasoning payload (signed thinking blocks in the provider’s history-replay representation). Appended to ChatResponse::reasoning_content for the next provider request and never surfaced as user-visible progress.

ToolCall(ToolCall)

Structured tool call emitted during streaming.

PreExecutedToolCall

A tool call that was already executed by the model_provider (e.g. Claude Code proxy). Emitted for observability only — not re-executed by the agent’s dispatcher.

Fields

name: String

args: String

PreExecutedToolResult

The result of a pre-executed tool call.

Fields

name: String

output: String

Usage(TokenUsage)

Token usage reported by the provider, typically just before StreamEvent::Final. Providers that do not surface usage in streaming responses simply omit this event.

Final

Stream has completed.

Implementations

impl StreamEvent

pub fn from_chunk(chunk: StreamChunk) -> StreamEvent

Trait Implementations

impl Clone for StreamEvent

fn clone(&self) -> StreamEvent

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for StreamEvent

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.